GB466097A - Improvements in the manufacture of dyes - Google Patents

Abstract

Dyes having the structure <FORM:0466097/IV/1> [where A=an aryl residue, X= S or Se, Y=alkyl or alkoxy, substituted or not (but not including CCl3 or CH3.CH=CH--), Z=O or S, R=alkyl and P and Q are the same or different monovalent organic radicals or are members of a common heterocyclic or homocyclic ring] are made by condensing with an arylthiazoline or an arylselenazoline having a ketonic alkacylmethylene group attached to the carbon atom in the a -position to the azoline nitrogen atom and an alkyl group attached to the azoline nitrogen atom, a compound containing a reactive methylene group directly attached to a --CO or --CS group and selected from among the following: the barbituric acids (including thiobarbituric acid), aroylacetonitriles, rhodanines and 2-thio-2 : 4-oxazolediones. They show a novel sensitizing action in photographic silver salt emulsions, and are useful in the construction of light filters. They also dye textiles, e.g. cellulose acetate artificial silk. According to examples: (a) 1-acetylmethylene-2-ethylbenzthiazoline is condensed in acetic anhydride with thiobarbituric acid, 3-ethylrhodanine, 3-phenylrhodanine or 3-ethyl-2-thio-2 : 4-oxazoledione; (b) 2-acetylmethylene - 1 - ethyl-b -naphthathiazoline is similarly condensed with thiobarbituric acid, benzoylacetonitrile, rhodanine, 3 - ethylrhodanine, 3 - phenyl-rhodanine or 3-ethyl-2-thio-2 : 4-oxazoledione, (c) 1-ethyl-2-propionylmethylene-b -naphthathiazoline is condensed with 3-phenylrhodanine. The condensation of 1-acetylmethylene-2-ethylbenzthiazoline with barbituric acid is also indicated in an equation. Specifications 428,222 and 466,269 are referred to. The reaction may be represented as follows <FORM:0466097/IV/2> where R<1> = an arylthiazole or arylselenazole system, H2C< = a reactive methylene group and X = alkyl or alkyloxy. According to the Provisional Specification an a -acylmethylene derivative of a cyclic nitrogen base, especially of an azoline, having a substituent, e.g. alkyl, on the nuclear nitrogen atom is condensed with a compound containing a reactive methylene group directly attached to a --CO or --CS group, especially an intracyclic reactive methylene group in a heterocyclic nucleus.